ION EXCHANGE MEMBRANE FOR POLYBENZIMIDAZOLE-BASED REDOX BATTERY, METHOD FOR PRODUCING THE SAME, COMPOSITE BODY, AND REDOX BATTERY

摘要

PROBLEM TO BE SOLVED: To provide an ion exchange membrane for a vanadium-based redox battery, excellent in energy efficiency and oxidation resistance, low in resistance, and suppressed in permeation of vanadium ions.SOLUTION: A method for producing an ion exchange membrane for a redox battery includes the steps of; adding 1-50 pts.wt. of one or more additives selected from among an inorganic salt, an alkali, and an organic base with respect to 100 pts.wt. of polybenzimidazole into a polybenzimidazole solution comprising constituent components that include a tetravalent aromatic group unit capable of forming an imidazole ring, a divalent aromatic group and one or more ionic groups, the constituent components being represented by formula (1); and removing the additives after forming a film from the solution by a discretionary method. (In the formula (1), Rrepresents a tetravalent aromatic group unit capable of forming an imidazole ring; Rrepresents a divalent aromatic group; X represents one or more ionic groups selected from among a sulfonic acid group, a phosphonic acid group, a hydroxyl group, a carboxyl group, or a metal salt or ammonium salt thereof; and m represents an integer of 1-4.)SELECTED DRAWING: None